Manufacture of rubber



Patented June 12, 1923.

v 7 1,458,693 PATENT OFFICE.

WILLIAM FELDENHEIMER, or LONDON, WALTER WILLIAM rLownAN, or EAST snnnmnnn PHILIP sennmowh'z, or LONDON, ENGLAND.

MANUFACTURE OF RUBBER.

No Drawing.

To all whom it may concern Be it known that W8,'WILLIAM' FELDEN- HEIMER, WALTER VVILLIAM PLOWMAN and PHILIP SonwRowrrz, sub'ects of the Kin of England, residing at iondon, Englan East Sheen, Surrey, England; and London, England, have invented certain new and useful Improvements in the Manufacture of Rubber, of which the following is a specification.

The present invention is for improvements in or relating to the manufacture of rubber, and concerns the production of rubber compositions containing clay.

According to this invention, a process for the manufacture of rubber compositions containing clay is characterized by the addition to the rubber mixture of a watersoluble soap in the dry state, for example, an alkali oleate, or the equivalent of a watersoluble soap, for example, an alkali and an acid or acids capable of yielding a soap.

The term water-soluble soap as hereinafter employed includes such equivalents.

in conjunction withthe soap an alkali,

for example, anhydrous sodium carbonate,

may be added mixture.

Prior to addition to the rubber mixture, the soap or the alkali or both may be incorporated in the dry state with the clay or a part thereof.

The clay may be prepared from any suitable natural clay by washing and sedimentation or other process which is adapted to give a pure product, but preferably the clay utilized is one which has been prepared by aid of peptisation (deflocculationg.

By peptisation is meant the ispersion in the dry state to the rubber of the clay in a fluid medium by addition of an appropriate quantity of a peptising (deflocculating) reagent, for example, am monia, sodium hydrate, or sodium carbonate. The clay substance is then recovered from the dispersion in any known way. Clay the preparation of whlch has involved treatment of this kind is hereinafter referred to as colloidal clay.' For example, clay which has been submitted to the processes set forth in-.Feldenheimers specification of British Letters Patent No. 106,890, or No. 121,191 (United States Patent No. 1324958) may be used.

The followin dicate two mod examples will serve to ines of procedure according Application flled August 12, 1921. Serial No. 491,829.

to this invention, ,is being understood that these examples are given for illustrative purposes and not by way of limitation.

' Example I To a china-clay prepared accordin rto the UnitedStates Patent No. 1324958, t ere was added an intimate admixture of anhydrous sodium carbonate and sodium oleate in such proportion as to give a ma- Parts.

Rubber 57 Treated clay 4O Sulphur 3- This mixture on vulcanziation at 40 lbs. pressure gave a correctly cured composition in about 45 minutes.

Example I I The mixture had the following composition:

Parts.

Rubber 228 Colloidal clay 151 Sodium carbonate (anhydrous) 4.5 Oleic acid 4.5 Sulphur 12 The colloidal clay was clay p repared according to the aforesaid atent No. 1,324,958.

. The sodium carbonate was intimately admixed with the clay by grinding the two together, the treated clay was introduced into the mixer and the ingredients were then incorporated together, the oleic acid being added drop by drop during the process of mastication.

On vulcanization at 40 lbs. pressure the mixture was fully cured in from 60-75 minutes.

The proportion relatively to the clay of the soap constituent of the mixture may be varied as required, a preliminary t r1al serving to determine this factor 1n a given case, for example, according to the constitutlon of the mixture or the nature of the rubber composition desired. As a guide, 1t may be The so treated clay was saidthat relative 'set forth in the a which have been found to give good comroportions of the order bove examples are those bined results, decreasing the relative proortion of the soap constitutent tending to increase the time of cure, while as the proportion is augmented the rate of the cure generally rises, and if the relative quantity of this constituent be too high the rate of curin may be increased at the ex use of the p ysical properties of the fine composition.

By the manufacture of rubber compositions according to this invention, products areobtainable of high breakin strain and good distensibility, which both b their appearance and physical roperties are adaptable for various technical applications.

What we claim' as our invention and desire to secure by Letters Patent is 1. The process for the manufacture of rubber compositions which comprises the incorporation of clay in conjunction with a saponaceous material in the dry state with a rubber mixture.

2. The process for the manufacture of rubber compositions which comprises the incorporation of colloidal clay in conjunction with a saponaceous material in the dry state witha rubber mixture.

3. The process for the manufacture of rubber compositions which comprises the incorporation of colloidal clay in conjunction with an alkaline saponaceous material in the dry state with a rubber mixture.

y 4. The. process for the manufacture of rubber compositions which comprises the incorporation ofcolloidal clay in conjunction with an alkali soap in the dry state with a rubber mixture.

5. The process for the manufacture of rubber compositions which comprises the incorporation of colloidal clay in conjunction w1t a rubber mixture. 1 p

6. The process for the manufacture of rubber compositions which comprisesthe inco ration of colloidal clay in conjunction wit an alkali and an alkali oleate in the dry state with a rubber mixture.

The process for the manufacture of rubber compositions which comprises in-' corporatin colloidal clay with an alkali and an alkali 0 cats in the d? state then incorporatm the product wit a' rubber mixture, and vu canizmg the mass.

8. The process for the manufacture of a an alkali oleate in the dry state with rubber composition which comprises compounding clay and a saponaceous substance with a vulcanizable mixture of unvulcanized rubber, and vulcanizing the mass.

9. The process for the manufacture of a rubber composition which comprises compounding c y and a substantially dry sa onaceous substance with a vulcanizable mixture of unvulcanized rubber, and vulcanizin the mass.

10. rubber composition which comprises compounding colloidal clay and a substantially dry saponaceous substance with a vulcanizable mixture of unvulcanized rubber, and vulcanizing the mass. y

11. The process for the manufacture of a rubber composition which comprises compoundin colloidal clay and-a substantially dr alka ine saponaceous substance with a vu canizable mixture of unvulcanized rubber, and vulcan-izin the-mass. 12. The process or the manufacture of a rubber composition which comprises compounding colloidal clay and a substantially dry salt of a fat-derived acid and an alkaline base with a vulcanizable mixture of unvulcanized rubber, and vulcanizing the mass.

13. The process for the manufacture of a rubber composition which comprises compounding colloidal clay and a substantially dry alkaline oleate with a vulcanizable mixture of unvulcanized rubber, and vulcanizing the mass.

14. The process for the manufacture of a rubber composition which comprises compoundin colloidal clay and a substantiall dry alka ine oleate-and alkali with a vu e process for the manufacture of a canizable mixture of unvulcanized rubber,

dry sodium oleate and carbonate with a vii canizable mixture of unvulcanized rubber, and vulcanizing the mass.

In testimony whereof we have signed our names to the s ification.

WILLIA FELDENHEIMER. WALTER WILLIAM PLOWMAN. 4 PHILIP SCHIDROWITZ. 

